This section provides background information related to the present disclosure which is not necessarily prior art.
Providing alternative light sources is an important goal to reduce energy consumption. Alternatives to incandescent bulbs include compact fluorescent bulbs and light-emitting diode (LED) light bulbs. The compact fluorescent light bulbs use significantly less power for illumination. However, the materials used in compact fluorescent bulbs are not environmentally friendly.
Various configurations are known for light-emitting diode lights. Light-emitting diode lights last longer and have less environmental impact than compact fluorescent bulbs. Light-emitting diode lights use less power than compact fluorescent bulbs. However, many compact fluorescent bulbs and light-emitting diode lights do not have the same light spectrum as incandescent bulbs. They are also relatively expensive. In order to achieve maximum life from a light-emitting diode, heat must be removed from around the light-emitting diode. In many known configurations, light-emitting diode lights are subject to premature failure due to heat and light output deterrents with increased temperature.
Energy Star has purposed luminous intensity distribution requirements for omni-directional lamps. The luminous intensity is measured within each vertical plane at a five degree vertical angle increment from 0° to 135° degrees. This is illustrated in FIG. 1. Ninety percent of the measured intensity values may vary by no more than 25% from all the average of the measure values in all planes. The measurements repeated in vertical planes about the lamp polar axis in maximum increments of 22.5° from 0° through 180°. Meeting the requirements particularly in the range from 180° to 135° is difficult with light emitting diode based lamps due to the inherent directionality of the light output of a light emitting diode.